Hydraulic pump and motor type governors



June 8, If? B. E. KNIGHT 2,713

HYDRAULIC PUMP AND MOTOR TYPE GOVERNORS Filed March 2, 1953 Unitcd States Patent HYDRAULIC PUMP AND Moron TYPE GGVERNGRS Basil Edward Knight, Eastcote, Pinner, England, assignor to C. A. V. Limited, London, England Application March 2, 1953, Serial No. 339,884

Claims priority, application Great Britain March 7, 1952 2 Claims. (Cl. 264-44) This invention relates to hydraulic governors for controlling the output of a variable delivery liquid fuel injeciion pump for an internal combustion engine, or for other purposes.

The object of the invention is to enable the governing action to be regulated in a simple and convenient manner.

A governing means in accordance with the invention comprises the combination of a cylindrical and springloaded throttle which is slidable and rotatable in a bore for controlling a port in the bore, and an angularly movable cam associated with the throttle, angular movement of the throttle being effected either by manual actuation of the cam or by axial movement of the throttle relatively to the cam in response to the pressure of liquid acting on the throttle.

In the accompanying drawing:

Figure l is a sectional side elevation illustrating an application of the invention to a liquid fuel injection pump for an internal combustion engine.

Figure 2 being a cross section on the line 2-2 Figure l, and Figure 3 being a part sectional end view.

Figure 4 is a plan of the cam shown in Figures 1 and 2.

The pump to which the invention is applied as shown in the drawing is of a known kind and includes a plurality of reciprocatory plungers (not shown) contained in a body part a. Motion is imparted to the plungers by a cam shaft driven by the engine, and the output of the pump is regulated by a slidable rod b which serves to impart angular movements to the plungers for varying their relation to spill ports in the pump barrels. In the present example, the governor forming the subject of the invention is required to actuate the rod b when a given engine speed is reached for reducing the pump output.

In carrying the invention into effect as shown in the drawing, there is attached to one end of the pump body a governor housing 0 which includes a chamber d, this being filled with liquid fuel supplied by a passage e connected to the pump-supply pipe. In line with the control bar b there is formed in the housing 0 a cylindrical bore 1, and liquid is supplied to the left hand end of the bore f by a gear pump g, which is driven by a shaft 11, which may be the cam shaft of the pump, or a shaft driven by the cam shaft. Liquid is supplied to the pump from the chamber d through a passage 1, and is delivered by the pump to the said bore f along a passage i at a pressure related to the speed of the pump. The liquid is returned from the bore 1 to the chamber d through a port j (Figures l and 3). To avoid the occurrence of an excessive pressure in the bore 1, a spring loaded relief valve k is provided between the passage i and the chamber d.

In the bore f is contained a cylindrical throttle m which at one end is loaded by a spring 12 and which at the other end is connected to the pump control bar b. In the periphery of the throttle is formed a longitudinal groove 0 which is open to the left hand end of the bore, and which by angular movement of the throttle is adapted to vary the effective area of the port and consequently 2,711,894 Patented June 28, 1955 ice to vary the resistance to the rate or" flow of the liquid through the port.

On the end of the throttle which extends beyond the bore f is formed or secured an arm p which is loaded by a spring q. One end of the arm 2 abuts against one side of an angularly movable cam r shaped as shown, or made to any other appropriate form, the cam being operable manually by a lever s which is movable between a pair of adjustable stops t on the exterior of the housing c.

The arrangement is such that the initial angular position of the groove 0 relatively to the port i can be varied by angular movement of the cam. Also longitudinal movement of the throttle to the right by the liquid pressure is accompanied by angular movement of the throttle in the direction for restricting the effective area of the port j.

A given setting of the cam determines the speed at which the bar b will be actuated for reducing the pump output. With increasing speed of the pump the pressure at which liquid is supplied by the pump g to the left hand end of the bore 7 increases, and when the pressure is sulficient to move the throttle against the action of the spring n, this movement results in the desired actuation of the control bar b for reducing rate of output of the pump. At the same time the movement of the throttle arm 2 along the cam results in increased restriction or closing of the port j. With fall of speed the throttle is returned by the spring 11, and the bar b is thereby moved in the direction for increasing the rate of output of the pump.

Whilst the invention is primarily intended for use in controlling the output of a variable delivery liquid fuel injection pump, it is not restricted to such use, as it may be applied to other uses where it is required to regulate the rate of flow of a liquid along a passage under manual control and in response to the pressure of the liquid.

Having thus described my invention what I claim as new and desire to secure by Letters Patent is:

l. A hydraulic governor comprising in combination a body part having formed therein a bore provided with a liquid outlet port, a cylindrical and spring-loaded throttle slidable and angularly movable in said bore for varying the efiective area of said port, means for supplying liquid under pressure to said bore at one end of said throttle, an angularly adjustable cam, and means co-operating with said cam for imparting angular movement to said throttle in response to both sliding movement of said throttle and angular adjusting movement of said cam.

2. A hydraulic governor comprising in combination a body part having formed therein a bore provided with a liquid outlet port, a cylindrical and spring-loaded throttle slidable and angularly movable in said bore for varying the effective area of said port, the periphery of said throttle being formed with a longitudinal groove which is open at one end of said throttle, and which co-operates with said port for controlling communication thereof with the interior of said bore, a pump for supplying liquid under pressure to said bore at the said end of said throttle, an angularly adjustable cam having manually operable actuating means, and a spring-loaded arm provided on said throttle and co-operating with said cam for imparting angular movement to said throttle in response to both sliding movement of said throttle and angular adjusting movement of said cam.

References Cited in the file of this patent FOREIGN PATENTS 248,144 Great Britain Mar. 4, 1926 463,310 Great Britain Mar. 24, 1937 475,693 Great Britain Nov. 24, 1937 

